fischer



(No Model.) 3 SheetsSheet 1.- S. FISCHER. ELECTRIC CLOCK Patented Apr.26,1 98.

INVENTOR ATTORNEYS 3 S11eets-Sheet 2.

S. FISCHER.

ELEGTRIG CLOCK.

No, 603,232. Patented Apr. 26, 1898.

I2 llllllllllf (N0 Model.) 3 Sheets-Sheet 3.

' S. FISCHER.

ELECTRIC CLOCK.

Patented Apr. 26, 1898.

iNVENTOR- I ATTORNEYS.

UNITED STATES PATENT OFFICE.

SIGISMUND FISCHER, OF NE\V YORK, N. Y.

ELECTRIC CLOCK.

SPECIFICATION forming part of Letters Patent No. 603,232, dated April26, 1898.

Application filed June 26, 1897.

To all whom it may concern.-

Be it known that I, SIGISMUND FIseHER, a citizen of the United States,residing in the city, county, and State of New York, have inventedcertain new and useful Improvements in Electric Clocks, of which thefollowing is a specification.

This invention relates to certain improvements in the electric clock forwhich Letters Patent No. 555,313, dated February 25, 1896, were grantedto me, said improvements being designed with a View of improving thedrivin g mechanism of the going-train of the clock,

the regulation of the motion of the minute and seconds hands, and thesynchronizing of said hands by a switch operated either by hand orautomatically from a master-clock whenever the minute and seconds handsarrive at zero.

My invention consists of an electric clock having a synchronizingelectromagnet and an arm extending radially from the minutehand arborand provided at its outer end with an armature adapted to be attractedby said magnet for moving the minute-hand forward or backward to a givenpoint of time, so as to synchronize with a master or other clock; andthe invention consists of certain features of construction andcombinations of parts to be hereinafter described and then particularlyclaimed.

In the accompanying drawings, Figure 1 represents a front elevation ofthe clock-move ment of my improved electric clock with the dial removedand some parts broken away, so as to show the operating parts beneaththe same. Fig. 2 is a side elevation of Fig. 1. Fig. 3 is an elevationof the going-train of my improved clock, partly in section on line 3 3,Fig. 2, and showing the driving mechanism of the clock. Fig. 4 is adetail of the mechanism by which the electric impulses are imparted tothe pendulum. Fig. 5 is a detail front view of the synchronizing devicefor the seconds-hand. Figs. 6 and 7 are top views of the same, showingthe same respectively in normal position and in the act ofsynchronizing. Figs. 8, 9, 10, and 11 are details of the mechanism foralternately throwing the different batteries by the current of which theclock is driven into action. Figs. 12, 13, a'nd13" are details of thedriving mech- Serial No. 642,386. (No model.)

anism. Figs. 14, 15, 16, 17, 18, and 19 are additional details, drawn ona larger scale, of the synchronizing mechanism of the seconds-hand.Figs. 20 and 21 are a vertical transverse section and a front elevationof the synchronizing mechanism of the minutehand, and Fig. 22 is adiagram showing the electric connection of the clock and synohronizingdevices with the batteries by which electric current is supplied.

Similar letters of reference indicate corresponding parts.

Referring to the drawings, Arepresents the frame of my improved electricclock, which is supported on an iron casting or plate B, which isscrewed to wooden back of the clockcase. From a horizontal support I) atthe upper part of the casting B is suspended the pendulum P in the usualmanner. The pendulum-rod is engaged by a pin 0 on a crutch C, the upperend of which is attached to a spindle cl, that turns in bearings of thesupportingframe A. On the spindle d is mounted a bar armature E, whichis arranged between the pole-faces of an electromagnet E, that isattached to the casting or supporting-plate B of the clock. The ends ofthe armature E, as well as the pole-faces of the electromagnet E, aremade equidistant from either side of the axis of the spindle d, so thatthe ends of the armature can pass by said pole-faces as the armature isoscillated by the beats of the pendulum.

On the crutch O is arranged a pin F,which is made wedge or knife edgedand adapted to engage a notched or bifurcated pendant F, which ispivoted to the inner end of a fulcrumed contact-lever F, the outer endof which is provided with a platinum point f that presses on acontact-spring f whenever the pendant engages the pin F on the crutch,said contact-spring being insulated from the clock-frame by theinsulating-block f on which it is fixed. One bifurcation of the notchedpendant is made somewhat longer than the other bifurcation, so that thependant is only engaged by the pin F when the pendulum moves in onedirection, but cannot be engaged by the return beat of the pendulum. Alight spring F supported at one end on the frame A, bears by its freeend on the contact-lever F in such a manner as that in case of thepivots being clogged by oil or otherwise there will be a perfectelectrical connection between the said lever and frame, while at thesame time it acts to return the lever to normal position for breakingcontact. An adjusting-screw f is arranged adjacent to and bearing on thecontact-spring f for setting the latter relatively to the contactpoint f2 on the lever and thus regulating the contact. Whenever the platinumpoint f 2 of the contact-lever F is pressed against the spring f thecircuit with the driving battery is closed, so that the current of thesame passes from one pole of the battery to the clock-frame, thenthrough lever F to the insulated contact-spring f thence through theclam ping-clip f and suitable metallic connections to the coils of theelectromagnet E, and then back to the other pole of the battery. (SeeFig. 22.) As soon as the circuit is closed the current energizes theelectromagnet, so that the poles of the same attract the armature E andimpart a turning motion to the same on its spindle and thereby throughthe crutch C an impulse to the pendulum.

Upon the arbor d of the crutch G of the pendulum P is applied across-piece g, that carries two gravity push-pawls g 9 which are pivotedto the cross-piece at opposite points and equidistantly from the spindled, said cross-piece being secured to the crutch-spindle by a suitableset-screw. The pawls alternately engage the teeth of the drivingspurwheel G, by which, in connection with suitable transmitting-gear,the necessary motion is imparted to the arbor of the minute-handmechanism to the arbor of the hour-hand.

When the push-pawls and driving spurwheel are used in a clock-movementhaving a seconds-hand, the spur-wheel G is applied directly to the arborof the seconds-hand, the pawls. being arranged so as to work in the sameplane with the spur wheel, as shown in Fig. 3, When used in aclock-movement without seconds-hand, the motion-transmitting beveledgear-Wheel, as shown in Fig. 3,

is dispensed with, and pawls of special shape of the spur-wheel G areused, said spur-wheel having in this case a horizontal or nearlyhorizontal position on its arbor, as shown in Fig. 12. In the place ofthe horizontally-projecting teeth on the spur-wheel G the teeth may bebent up at an angle with the plane of the wheel, so as to form acrown-wheel with ratchet-teeth by which the driving motion is impartedto the clock-train.

By the double-push-pawl device described a forward motion is imparted tothe hands at each beat of the pendulum, the advance of thespur-wheelbeing one-half tooth for each singlebeat of the pendulum. This res-1.113 is obtained because while one pawl engages the spur-wheel the othermoves backwardly over a tooth of the spur-wheel, and vice versa. By thisarrangement it is possible to give a correct motion to the seconds-hand,so as to divide the minute properly, as indicated on the seconds-dial.With the use of a single driving-pawl in conjunction with a fixedcheckpawl motion would be imparted to the hands by the driving-pawl onlyonce for each alternate beat, so that in a clock having a pendulum oflength to beat seconds, or sixty times per minute, the seconds-handwould only be moved thirty times per minute, or once every two beats ofthe pendulum. By using the double push-pawl, however, the minute isaccurately divided into seconds, and the seconds-hand is moved with eachbeat of the pendulum. The same proportion is maintained when usingshorter pendulu ns-as, for instance, with an eighty-beat pendulum theminute is divided by fractions less than seconds by this device, so thatthe time may be accurately measured by the seconds-hand, whereas thesingle drive-pawl would give only forty motions per minute, or more thanone second for each motion of the secondshand. By employing thedouble-pusl1-pawl device the check-pawl may be dispensed with,

i as each pawl acts in its turn as a check-pawl for the other pawl. ofthe pendulum is more evenly divided, in-

Furthermore, the work asmuch as it moves the clock-train forward atevery beat instead of by every second heat. Imovement of theminute-hand, which is an advantage, especially in the ease of largeclocks having long hands, so as to make the advancing motion of theminute-hand less a noticeable.

and from the same by the usual transmitting j This produces also a morefrequent lhe synchronizing device by which the hands are electricallyset at certain intervals ;of time, so as to be placed in synchronismwith a master or other clock, is composed of two separate andindependent mechanisms, one for setting the minute hand and theiotherfor setting the seconds-hand. In clocks Twithout seconds-hands thelatter mechanism is not required, while for clocks having seconds-handsboth the mechanism for synchronizing the minute and seconds hands are 3used. that engage the teeth or notches in the side i The minute and hourhands synchronizer A plate M, forming the outer The rear andelectromagnet in front of the front plate of the clock-frame, so as topermit an armature M,which is made in the shape of an arm and providedwith an enlarged lower end, to move through said space in following themove 'ment of the minute-hand arbor, to which said armature is rigidlyapplied. The armature M is arranged diametrically in line with theminute-hand and applied by a brass clip 1% to the arbor of theminute-hand, as shown clearly in Fig. 2.

In place of the bar electromagnet a horseshoe or bipolar electromagnetmay be used, in which case the armature has to be attracted by thecombined means of the polefaces,'so as to sweep across the same. Thearmature M is located on the arbor of the minute-hand back of the dial,so that it is not seen during the rotation of the minutehand.

The described method of supporting the transmitting gear-wheels by whichthe motion is transmitted from the minute-hand arbor to the hour-handsleeve, as shown in Fig. 2, leaves a sufficient clearance for thearmature h as the same moves around with the minute-hand, which wouldnot be the case if said gear-wheels were arranged in the usual mannerupon the front plate of the clockframe.

The coil of the electromagnet M is connected with a suitable electricbattery W and with a main wire, which is connected with a suitableswitch S, as shown in the diagram Fig. 22. The switch is either workedin the usual way by hand, whenever it is desired to synchronize theclocks, or automatically by being connected electrically with amasterclock. The closing of the circuit and the time-signals are givenexactly at the even hour. In case the clock to be synchronized should bea little too fast or too slow, the momentary closing of the switchcauses a current to flow through the electromagnet M, so as to energizethe core of the same and attract the enlarged end of the armature, so asto set thereby the hand to point exactly to the even hournamely, 12 orzeroas the armature is attracted and placed with the hand into verticalposition by the pole end of the electromagnet. The armature M may beadjusted laterally on the arbor of the minute-hand by means of set-screwm, so as to be slightly adjusted relatively to the position of theminute-hand, so that when it is exactly at rest or at the dead-pointover the pole face or faces of the electromagnet the minute-hand willpoint exactly to 12 or zero. The armature M is also capable ofadjustment in longitudinal direction, as its upper end is attached by ascrew m to a socket on the clip m, as shown in Figs. 20 and 21, so as tobring the enlarged lower end of the armature as close as possible to thepole face or faces of the electromagnet without touching the same,reducing thereby the airspace between them to a minimum. As the closingof the switch takes place for only a fraction of a second, the armatureis immediately released again from the attraction of the electromagnetM, so that the minutehand is at liberty to move over the dial as before.

The minute-hand arbor is thus free to be moved by the synchronizingelectromagnet without interfering with the action of the clock-movementon account of the usual friction-spring device, the tension of which ispreferably as light and even as possible. The armature M serves also asan internal concealed counterpoise for the minute-hand, so as to do awaywith the unsightly external visible counterpoise which is usuallyemployed on the hands of large clocks. The armature is preferably madeof the same weight as the minute hand, so as to balance the same andpermit thereby the easy movement of the minute-hand on its arbor.

The seconds-hand synchronizing device is in the same circuit with thesynchronizing mechanism for the minute and hour hands, so that both setsare actuated at the same instant. The seconds-hand synchronizer consistsof a specially-shaped thimble 473, which is attached to the outer end ofthe secondshand arbor which carries the seconds-hand, so that the twoparts turn together, the whole being mounted upon the front end of theseconds-hand arbor either by the usual friction and tension device or bymeans of the mechanism shown in Figs. 14 to 17. The thimble n is cutaway at one side, so as to form a slot in which rests one leg of a Ushaped tensionspring 92 which bears upon the seconds-hand arbor, whilethe opposite leg bears upon the outer surface of the thimble. This Ushaped spring by abutting against a shoulder or enlargement n on theseconds-hand arbor serves to keep the parts on said arbor and furnishesat the same time the required tension and friction, which may beaveraged according to the stiffness of the spring employed. The thimblen is provided with a cam portion 91, having converging and slantingcam-faces 1%, that are engaged by a knife-edge, roller, or other device0, which is applied by a shank and set-screw 0 into a socket of anarmature P (see particularly Figs. 18 and 19) of an electromagnet P,which is supported by an extension-bracket attached by fastening-screwsto the front plate of the clock-frame. The armature P is hinged at theouter end of the eX- tension and actuated by means of a spring 3 so asto keep it away from the pole-face of the projecting core of theelectromagnet. The electromagnet may be made in the shape of a barmagnet with single pole or in the shape of a horseshoe with two poles orin any other shape. The extent to which the armature may move away fromthe pole-face of the electromagnet is regulated by a stud P having anenlarged end P which passes through a slot P in the armature, said studbeing applied to the bracket or extension of the frame. The headed studP together with the guideslot in the armature serve to guide thearmature, so as to prevent any lateral play of the same in itsforward-and-backward motion when attracted or released by the pole. Theknife-edge is applied to the inwardly-projecting end of the armature,which is made long enough so as to extend to a point directly oppositethe cam-faced friction-thimble n on the arbor of the seconds-hand. Whenthe armature is attracted by the closing of the circuit and theenergizing of the pole of the electromagnet, the knife-edge or rollerwill bear on either one of the'i'nclined or cam faces of thefriction-thimble and turn it around, carrying the seconds-hand with ituntil the limit of motion is reached,when the knifeedge or rollerarrives at the converging inner ends of the inclined, slanting, or camfaces and can go no farther, as shown in Fig. 7. When the seconds-handis therefore at either side of the zero or sixty-seconds point of theseconds-dial, the action of the armature on the cam-faces of thefriction-thimble will move it exactly up to zero and thereby synchronizethe seconds-hand simultaneously with the minute-hand. As the switch isimmediately opened again after being closed, the current is interruptedand the armature moved out of engagement with the frictionthimble, sothat the seconds-hand can move on in the usual manner.

arbor, so as to form a kind of automatic switch by which the current isapplied alternately from one battery or the other at regular in-. Ifthree batteries are em-E tervals of time.

ployed, as shown in Fig. 22, the three projectmg segments are arrangedon the sleeve V of the minute-hand arbor, as shown clearly in detail inFigs. 8, 9, 10, and 11. the segments are applied to the hub of thecenter wheel, which extends in the form of a sleeve over the minute-handarbor. The

In this case raised segments on the sleeve V are arranged parallel witheach other and extend circum-- ferentially around the sleeve, but arelocated at different points on the circumference of the same, they beingof a length slightly less than one-third of the circumference of thesleeve, so that spaces or intervals are formed between the planes of theadjacent ends of the segments. insuch a position to each other that onlyone at a time is'engaged by one of three contactbrushes T, which areapplied to an insulatingblock T, that is pivoted tothe frame of theclock between the front and intermediate plate of the same, as shown inFigs. 2, 3, 8, and 9. The contact-brushes T are non-elastic and rigidlyattached to the insulating-block, which latter is actuated by atension-spring if, so that the brush which is in action presses evenlyagainst its corresponding segment on the sleeve V. Thecontact-brushesare each connected with the poles of the three batteries,theenlarged ends extending vertically over the center of the sleeve, sothat each forms contact with the segments 0* on the same as The segmentsare thereby arranged the sleeve is rotated. During the rotation of thesleeve V one segment 0' after the other is brought into contact with itscontact-brush, so that at the instant one battery is cut out of thecircuit the next is switched in and at no time more than one battery isin circuit. This is accomplished by the brushes, as immediately when onecontact-brush drops off from the end of its segment the next one dropsonto the forward end of its segment. The segments project far enoughabove the sleeve V so that the brushes will not touch it when droppingfrom one segment to the next. The object of changing from one battery tothe other is to give each battery a chance to rest and recuperate atregular intervals, so as to prolong thereby the life of the batteriesand increase their effectiveness. When three batteries are used inconnection with springs having three segments, each battery suppliescurrent for twenty minutes and rests forty minutes during every hour.

It is evident that without departing from the scope and spirit of theinvention the synchronizing of the minute-hand need not necessarilybeobtained at 12, for by setting the operating-electromagnet and thearmature at different angles to the arbor of the minutehand the same maybe accomplished at a different time.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. The combination, with the minute-hand arbor, of asynchronizing electromagnet, and an arm extending radially from the saidarbor and provided at its outer end with an armature, adapted to beattracted by said magnet for moving the minute-hand forward or backwardto a given point of time so as to synchronize with a master or otherclock, substantially as set forth.

2. The combination, with the minute-hand arbor, provided with a minute-hand, of a synchronizing electromagnet, and an armature applied to thesaid arbor diametrically in line with the said minute-hand and acting asa counterpoise, said electromagnet being arranged in the circledescribed by the armature, substantially as set forth.

3. The combination, with the arbor of the minute-hand, of asynchronizing electromagnet located adjacent to the same, an armatureextending radially from said arbor, and means for adjusting saidarmature longitudinally to and from the arbor and toward the pole of theelectromagnet, said magnet and armature cooperating to produce theforward or backward motion of the minute-hand and the synchronizing ofthe same with a master or other clock, substantially as set forth.

4:- The combination, with the arbor of the minute-hand, of asynchronizing electromag net located adjacent to the same, an armextending radially from the said arbor, means for adjusting the armaround the arbor, an armature, and means for connecting the armaturewith said arm and longitudinally adjusting the said armature toward thepole of the electromagnet, said magnet and armature producing theforward or backward movement of the minute-hand to the desired point oftime, substantially as set forth.

5. The combination, with the clock-frame provided with asupporting-bracket, of a synchronizing electromagnet attached to thebracket, a plate forming the outer clamping part of the bracket, andprovided with bearings for the intermediate transmitting mechanism ofthe hour-hand, said bracket and plate providing a space between them,and an armature attached to the arbor of the minute-hand and adapted tomove through said space, substantially as set forth.

6. The combination, with the seconds-hand cam-faces of saidfriction-thimble, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname in pres- 3o ence of two subscribing witnesses.

SIGISMUN D FISCHER.

Witnesses:

GEO. W. J AEKEL, CARL FABLE.

